it

名词 it:

1. the branch of engineering that deals with the use of computers and telecommunications to retrieve and store and transmit information
   同义词：information technology

1. Where's your car?' It's in the garage.'
   ｀你的汽车在哪儿呢?＇｀在车库里＇.
2. The baby next door kept me awake. It cried all night.
   隔壁的孩子吵得我睡不著觉。他整夜哭个没完
3. There is a rosebush near the fence and it is very beautiful.
   篱笆附近有一丛玫瑰，长得非常美丽。
4. It's Friday.
   今天星期五。

it

pron.（代词）
Used to refer to that one previously mentioned. Used of a nonhuman entity; an animate being whose sex is unspecified, unknown, or irrelevant; a group of objects or individuals; or an abstraction:
表示物体：用于指已经提到的事物。用于指无生命物体；性别不详、不知或不相关的有生命物体；事物和群体；抽象物质：
例句：
polished the table until it shone; couldn`t find out who it was; opened the meeting by calling it to order.
把桌子擦出光亮；查不出是谁；会议开始，全体肃立

Used as the subject of an impersonal verb:
表示主语：用作非人称代词的主语：
例句：
It is snowing.
正在下雪

Used as an anticipatory subject or object:
代主语或宾语：作为先行主语或先行宾语：
例句：
Is it certain that they will winô
他们一定会赢吗ô

Used as an anticipatory subject to emphasize a term that is not itself a subject:
强调主语：作为先行主语来强调，但它本身并不是主语：
例句：
It was on Friday that all the snow fell.
是在星期五下雪的

Used to refer to a general condition or state of affairs:
情况状态：用于指事情通常的情况或状态：
例句：
She couldn`t stand it.
她无法容忍

Informal Used to refer to something that is the best, the most desirable, or without equal:
【非正式用语】 指代事情：用于指最好的、最渴望得到的或者不平等的事情：
例句：
He thinks he`s it. That steak was really it!
他一直以为自己是最佳人选。那牛排真是不错！

n.（名词）
Games A player, as in tag, who attempts to find or catch the other players.
【游戏】 捉人者：一个想要发现或抓住其它人的游戏者，如在儿童的捉人游戏中
An animal that has been neutered:
被阉割的动物：
例句：
The cat is an it.
这只猫已被阉过

来源：
Middle English
中古英语
from Old English hit * see ko-
源自 古英语 hit *参见 ko-